1. Field of the Invention
The present invention generally relates to a method and apparatus for displaying a transmission route in a switched network and to a method of detecting a failure using such a method and apparatus.
More particularly, the present invention relates to a method and apparatus for displaying a transmission route in a ATM switched network formed by a fiber-optic cable, and a method of detecting a failure using such a method and apparatus.
2. Description of the Related Art
Asynchronous Transfer Mode (ATM) is known as a communication technology suitable for transmitting a large volume of data. In ATM, a fiber-optic cable is used to implement a communication channel (transmission channel).
Conventionally, a failure occurring on a route in an ATM switched network is performed by monitoring the number of ATM test cells generated by an ATM test cell generating apparatus and transmitted through an arbitrary communication apparatus and fiber-optic cable belonging to the ATM switched network. When it is found that the ATM test cells are not transmitted through the apparatus and cable at all, or when the volume of cells decreases as they are transmitted through the apparatus and cable, it is determined that a failure occurs.
In an ATM switched network, distribution of data is performed such that the hardware decodes destination information in an ATM header or an ATM tag in a tagged ATM cell to be transmitted. No error checking is performed for transferred bits. For this reason, a failure on a transmission route may not be found without examining the actual flow of ATM cells.
For example, even when the cable connection is seemingly proper, the ATM switched network may still have a failure. For example, the following problems may exist.
(1) Problem Due to a Bit Error Caused by Contamination of a Fiber-optic Cable
A bit error may be generated on a transmission route formed by a fiber-optic cable due to dust or the like. As mentioned above, such a bit error fails to be detected without causing ATM cells to flow in the transmission route. This means that detection of the bit error requires that communication apparatuses and fiber-optic cables be checked one by one while ATM cells are caused to flow in the network. For one-by-one checking of the communication apparatuses and fiber-optic cables, information relating to the arrangement of the communication apparatuses and fiber-optic cables on the transmission route and information relating to the connection of the fiber-optic cables should be available.
The information relating to the arrangement of the communication apparatuses and fiber-optic cables on the transmission route and information relating to the connection of the fiber-optic cables may be displayed in the form of graphical user interface (GUI) using data listing the arrangement of the apparatuses served by an ATM switch. While these information may be displayed as logical arrangement of the apparatuses or may indicate a detailed arrangement of the apparatuses served by the switch, it is difficult to accurately display the connection of cables between the apparatuses. For this reason, the experience of an operator may be relied upon for display of the arrangement and connection.
(2) Problem Relating to Improper Connection Due to Complex Connection
A plurality of ATM switches may be connected to form multiple stages in order to adapt for a large volume of traffic in a high-speed, advanced ATM switched network. In this arrangement, a large number of fiber-optic cables should be connected together. The communication capacity is proportional to the number of fiber-optic cables. However, when the number of fiber-optic cables is increased, an error in connecting cables or in replacing a failed cable is more likely to occur. An error in connecting cables brings about a failure in the switching performance of the ATM switched network. In order to resolve this, the arrangement of apparatuses and cable connection on a test route should be checked one by one. This involves a relatively large volume of work.
(3) Problem Relating to Input Error in Data Listing the Arrangement of Apparatuses Served by a Switch
Even when the physical arrangement of apparatuses served by the switch and cable connection are proper, the data listing the arrangement of apparatuses served by the switch may be improperly input. When such an error occurs, the system may be operated on wrong data listing the arrangement of apparatuses so that it takes time to find a problem. As new apparatuses are added to the network, the data is updated. Therefore, there is always a chance that an input error occurs. In order to identify an input error, it is necessary to examine the physical arrangement of apparatuses and cable connection one by one for possible errors, based on a drawing showing the arrangement of apparatuses and based on the information relating to the test route.
Accordingly, an object of the present invention is to provide a method and apparatus for displaying a transmission route for use in a switched network and a method of detecting a failure using such a method and apparatus, in which the aforementioned problems are eliminated.
Another and more specific object of the present invention is to easily and speedily identify a failure on a transmission route between any communication terminals without requiring an excessively large number of processes and resorting to the experience of an operator.
In order to achieve the aforementioned objectives, the present invention provides a transmission route display method for use in a transmission system wherein a display apparatus that provides a display responsive to a display command is provided in at least one of communication apparatuses and transmission routes in a switched network, comprising the steps of: one of said communication apparatuses in said switched network transmitting the display command to one of another of said communication apparatuses and the transmission route; and the display apparatus of said another of said communication apparatuses or the transmission route that received said display command providing a display so that a data transmission route over which said display command is delivered is indicated by the display.
The aforementioned objects can also be achieved by a failure detecting method for detecting a failure in a switched network, for use in a transmission system wherein a display apparatus that provides a display responsive to a display command is provided in at least one of communication terminals and transmission routes in the switched network, comprising the steps of: one of said communication apparatuses in said switched network transmitting the display command to one of another of said communication apparatuses and the transmission route; the display apparatus of said another of said communication apparatuses or the transmission route that received said display command providing the display; and detecting a failure in said switched network by examining a status of display occurring between a first communication terminal and a second communication terminal.
The aforementioned objects can also be achieved by a transmission route display system comprising: a switched network comprising communication apparatuses and transmission routes; and a display apparatus provided in at least one of said communication apparatuses and said transmission routes, wherein one of said communication apparatuses transmits a display command for causing the display apparatus of one of the communication apparatus and the transmission route to provide a display, an information analyzing unit is provided in at least one of said communication apparatuses and said transmission routes, and said information analyzing unit causes, responsive to the display command received from said one of said communication apparatuses, the display apparatus of one of another of said communication apparatuses and the transmission route to provide the display, so that a data transmission route over which said display command is delivered is indicated by the display.
The aforementioned objects can also be achieved by a transmission route display apparatus provided in at least one of communication apparatuses and transmission routes in a switched network, wherein an information analyzing apparatus is provided in at least one of said communication apparatuses and said transmission routes, and said information analyzing apparatus causes, responsive to a display command received from one of said communication apparatuses, the display apparatus one of another of said communication apparatuses and the transmission route to provide a display, so that a data transmission route over which said display command is delivered is indicated by the display.
The aforementioned objects can also be achieved by a communication apparatus comprising: an information analyzing apparatus; a display apparatus, wherein said information analyzing apparatus causes, responsive to a display command received from another communication apparatus, the display apparatus to provide a display, so as to indicate that said display command is transmitted through said communication apparatus.